No OCC needed if you have a FMIC

Nhe261 · 08-20-2014, 12:53 PM

Last time when I replaced the water pump I removed the FMIC and saw lots of oil on the bottom of the IC, I used a foam to suck it out when the IC was under sun heat. it is almost 1 oz oil. the FMIC has been installed for about half year.

IMO, when the hot air was cooled down, the oil vapar in the air will condense to liquid in the IC and catched by the IC fins. It will stay there until you drop it.

What do you guys think?

shadow191 · 08-20-2014, 01:16 PM

Part of the selling point of the catch can is so that you don't get oil pooling in the FMIC...But if you're ok with cleaning it all the time, I guess it's fine.

It does seem easier to empty a catch can vs. pulling the FMIC. I think I could take my catch can off, empty, and reinstall in 5 minutes (no cowl). How long does it take to drop the FMIC and mop it up?

TotalBlackout · 08-20-2014, 06:00 PM

Quote:

Originally Posted by shadow191

Part of the selling point of the catch can is so that you don't get oil pooling in the FMIC...But if you're ok with cleaning it all the time, I guess it's fine.

It does seem easier to empty a catch can vs. pulling the FMIC. I think I could take my catch can off, empty, and reinstall in 5 minutes (no cowl). How long does it take to drop the FMIC and mop it up?

Cleaning FMIC is free. It's a good idea to pull off even if you have an oil catch can. Not sure either philosophy makes an impact on carbon accumulation.

e92_enthusiast_1 · 08-20-2014, 06:06 PM

when you guys say clean it, do you mean literally run water through it and dry it out? Sorry if that's a dumb question but my new FMIC has been on about 5k miles so im just curious.

ferocity02 · 08-20-2014, 06:40 PM

Quote:

Originally Posted by e92_enthusiast_1

when you guys say clean it, do you mean literally run water through it and dry it out? Sorry if that's a dumb question but my new FMIC has been on about 5k miles so im just curious.

Water will sort of work, but something like kerosene or methanol will dissolve the oil and grease and get it much cleaner. Pour some in, shake it around, let it sit, repeat, then rinse with water and let it dry out in the sun. Or put it in the over at 250 to dry it out faster (don't do this with the stock IC due to the plastic end tanks).

e92_enthusiast_1 · 08-20-2014, 06:55 PM

Thanks for the clarification, sir

Quote:

Originally Posted by ferocity02

Water will sort of work, but something like kerosene or methanol will dissolve the oil and grease and get it much cleaner. Pour some in, shake it around, let it sit, repeat, then rinse with water and let it dry out in the sun. Or put it in the over at 250 to dry it out faster (don't do this with the stock IC due to the plastic end tanks).

noorj · 08-20-2014, 07:13 PM

Reasons to have a catch can

1:You don't want any oil in your intake system. If it gets ingested during WOT where air velocity is high enough to pull it in the engine will 100% knock. Knock at WOT results in extremely high cylinder pressures, enough to break shit.

Reason 2:Oil vapors that reach the intake valve are what form the carbon deposits, without a catch can this will happen very quickly and severely. With a catch can far less oil vapor makes its way thru the system to the intake valves, therefore less carbon deposits

tc535i · 08-20-2014, 07:16 PM

so oil being caught in a can vs oil accumulating in your compressed intake air route are pretty much the same thing?

might want to think this one over a little more

noorj · 08-20-2014, 07:26 PM

No they are not. Pressurized air is heavier and more turbulent, therefore can pull oil into oil vapors easier. When it is in the can, there is never enough negative pressure to pull into the intake track.

Nhe261 · 08-21-2014, 11:20 AM

Actualy last week when was replacing the AC compressor, I took all air system out until I can see very clearly on the intake valve, it is very very clean. Not even the sign of oil on the disk, i used a wiper try to clean it, there is nothing on it. When i installed the FMIC i cleaned it and it was kind of dirty about half year ago.
The FMIC is enough to cool down the air and condense the oil vapor and keep it in the lowest point of the IC, normally it's the discharge side of the IC and there is the coolest.
OCC will do more catching for sure but the shortage is to reduce the system pressure more because of the smaller area.

08-20-2014, 12:53 PM	#1
Nhe261 Second Lieutenant 17 Rep 201 Posts Drives: 2008 335i 4 door Join Date: Dec 2012 Location: SoCal iTrader: (1)	No OCC needed if you have a FMIC Last time when I replaced the water pump I removed the FMIC and saw lots of oil on the bottom of the IC, I used a foam to suck it out when the IC was under sun heat. it is almost 1 oz oil. the FMIC has been installed for about half year. IMO, when the hot air was cooled down, the oil vapar in the air will condense to liquid in the IC and catched by the IC fins. It will stay there until you drop it. What do you guys think?
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08-20-2014, 01:16 PM	#2
shadow191 Lieutenant Colonel 182 Rep 1,681 Posts Drives: 2017 Volvo XC90 R-Design Join Date: Dec 2012 Location: GA iTrader: (3)	Part of the selling point of the catch can is so that you don't get oil pooling in the FMIC...But if you're ok with cleaning it all the time, I guess it's fine. It does seem easier to empty a catch can vs. pulling the FMIC. I think I could take my catch can off, empty, and reinstall in 5 minutes (no cowl). How long does it take to drop the FMIC and mop it up?
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08-20-2014, 06:06 PM	#4
e92_enthusiast_1 Lieutenant Colonel 118 Rep 1,709 Posts Drives: '10 AW/CR e92 6mt 335i Join Date: Mar 2012 Location: Tempe, AZ iTrader: (1) Garage List 2010 BMW 335i [10.00]	when you guys say clean it, do you mean literally run water through it and dry it out? Sorry if that's a dumb question but my new FMIC has been on about 5k miles so im just curious. __________________ 2010 E92 N54 335i 6MT Alpine White 2025 G87 S58 M2 6MT Grigio Telesto - Ordered
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08-20-2014, 07:13 PM	#7
noorj calibrator 12 Rep 80 Posts Drives: 2007 E92 335i Join Date: May 2014 Location: Detroit iTrader: (1)	Reasons to have a catch can 1:You don't want any oil in your intake system. If it gets ingested during WOT where air velocity is high enough to pull it in the engine will 100% knock. Knock at WOT results in extremely high cylinder pressures, enough to break shit. Reason 2:Oil vapors that reach the intake valve are what form the carbon deposits, without a catch can this will happen very quickly and severely. With a catch can far less oil vapor makes its way thru the system to the intake valves, therefore less carbon deposits
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08-20-2014, 07:16 PM	#8
tc535i Lieutenant Colonel 222 Rep 1,818 Posts Drives: 2007 335i, 2001 330i, 1995 M3 Join Date: Sep 2013 Location: West Los Angeles iTrader: (1)	so oil being caught in a can vs oil accumulating in your compressed intake air route are pretty much the same thing? might want to think this one over a little more
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08-20-2014, 07:26 PM	#9
noorj calibrator 12 Rep 80 Posts Drives: 2007 E92 335i Join Date: May 2014 Location: Detroit iTrader: (1)	No they are not. Pressurized air is heavier and more turbulent, therefore can pull oil into oil vapors easier. When it is in the can, there is never enough negative pressure to pull into the intake track.
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08-21-2014, 11:20 AM	#10
Nhe261 Second Lieutenant 17 Rep 201 Posts Drives: 2008 335i 4 door Join Date: Dec 2012 Location: SoCal iTrader: (1)	Actualy last week when was replacing the AC compressor, I took all air system out until I can see very clearly on the intake valve, it is very very clean. Not even the sign of oil on the disk, i used a wiper try to clean it, there is nothing on it. When i installed the FMIC i cleaned it and it was kind of dirty about half year ago. The FMIC is enough to cool down the air and condense the oil vapor and keep it in the lowest point of the IC, normally it's the discharge side of the IC and there is the coolest. OCC will do more catching for sure but the shortage is to reduce the system pressure more because of the smaller area.
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